Composite light spot shaping system

Abstract

The invention discloses a composite light spot shaping system which comprises a first light source used for emitting a first light beam transmitted in a first channel, a second light source used for emitting a frequency doubling light beam transmitted in a second channel, and the first channel does not completely coincide with the second channel. The light beam shaping element is arranged in the first channel and / or the second channel and is used for adjusting the energy distribution of the fundamental frequency light beam and / or the frequency doubling light beam; the beam combiner is used for combining the fundamental frequency light beam and the frequency doubling light beam; and the focus lens is arranged at the output end of the beam combiner and used for converging the combined fundamental frequency light beam and frequency doubling light beam. By means of the composite light spot shaping system, fundamental frequency light beams without frequency doubling can be reused, the energy utilization rate is increased, point ring light spots are formed through the light beam shaping element, a welding pool is controlled, welding spatter is restrained, the point ring light spots with clear edges are formed through confocal of the light beam shaping element and the focus lens, energy is more concentrated, and the light spot shaping efficiency is improved. And the design and calibration process of the optical system is simplified.

Description

Technical Field

[0001] The present application relates to the field of light spot shaping, and in particular to a composite light spot shaping system. Background Art

[0002] In the field of fiber lasers, the processing of non-ferrous metals (aluminum, copper, etc.) is a research hotspot. Most mature fiber lasers on the market use near-infrared lasers of about 1000nm for processing operations. However, the absorption rate of non-ferrous metals to near-infrared light is only about 5%, which affects the processing effect. Studies have found that the absorption rate of non-ferrous metals to green light is more than 40%, which is significantly higher than that of near-infrared light. In the prior art, near-infrared light is usually doubled to green light through a frequency doubling crystal to greatly improve the absorption rate of metals to lasers. However, the frequency doubling efficiency of the frequency doubling crystal is not 100%, and the second fundamental frequency beam that has not been doubled will be absorbed and processed by the light trash can in daily operation, resulting in energy waste; the energy of the light source of a single light field is concentrated, which is easy to cause processing splashes. Therefore, in view of the insufficient utilization of fundamental frequency light in the prior art and the need for green laser spot shaping to adapt to more processing environments, it is necessary to design a composite spot shaping system. Summary of the invention

[0003] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a composite spot shaping system to solve the problems in the prior art of insufficient utilization of fundamental frequency light and the need for spot shaping of green lasers to adapt to more processing environments.

[0004] To achieve the above-mentioned purpose and other related purposes, the purpose of the present application is to provide a composite light spot shaping system, including: a first light source, used to emit a first light beam, the first light beam is transmitted in a first channel; a second light source, used to emit a second light beam, the second light beam is transmitted in a second channel, and the optical paths of the first channel and the second channel are different; a beam shaping element, arranged in the first channel and / or the second channel, for shaping the first light beam and / or the second light beam; a beam combiner, arranged at the beam output ends of the first channel and the second channel to receive the first light beam transmitted through the first channel and the second light beam transmitted through the second channel, and combine the first light beam and the second light beam; and a first focusing mirror, arranged at the output end of the beam combiner, for converging the combined first light beam and the second light beam, and the converged first light beam and the second light beam act on the processing surface.

[0005] Optionally, the beam shaping element can be translated along the optical axis to form a variable composite light spot on the processing surface.

[0006] Optionally, the beam shaping element comprises an axicon.

[0007] Optionally, the rear focal plane of the axicon coincides with the front focal plane of the first focusing mirror.

[0008] Optionally, the processed surface coincides with a back focal plane of the first focusing mirror.

[0009] Optionally, an optical path of the first light beam and the second light beam between a rear focal plane of the beam shaping element and a front focal plane of the first focusing mirror is not less than a focal length of the first focusing mirror.

[0010] Optionally, the composite spot shaping system also includes a laser source, a half-wave plate and a frequency doubling crystal arranged in sequence, the laser source is used to output a fundamental frequency beam, the half-wave plate is used to change the polarization direction of the fundamental frequency beam, and the frequency doubling crystal is used to double the fundamental frequency beam whose polarization direction is changed by the half-wave plate, and output the doubled beam and a second fundamental frequency beam that has not been doubled.

[0011] Optionally, a beam splitter is provided at the output end of the frequency doubling crystal for splitting the frequency doubling beam and the un-doubled fundamental frequency beam, the splitted frequency doubling beam is transmitted as the first beam in the first channel, and the splitted second fundamental frequency beam is transmitted as the second beam in the second channel.

[0012] Optionally, a second focusing mirror is provided between the half-wave plate and the frequency doubling crystal, for converging the fundamental frequency light beam whose polarization direction is changed by the half-wave plate and then injecting the light beam into the frequency doubling crystal.

[0013] Optionally, the fundamental frequency light beam output by the laser source is formed by combining continuous laser light and pulsed laser light.

[0014] Compared with the prior art, the composite laser processing system of the present application has at least the following beneficial effects: 1. The present application splits and shapes the frequency-doubled light beam and the second fundamental frequency light beam that has not been frequency-doubled, and then combines them for output, thereby utilizing the second fundamental frequency light beam that has not been frequency-doubled and is dispersed as stray light in the existing solution, thereby improving energy utilization; 2. Use the beam shaping element to shape the doubled frequency beam and the second fundamental frequency beam that has not been doubled frequency. The wavelength distribution and shape distribution of the formed composite light spot can be adjusted to adapt to a variety of processing environments; 3. A simple spot shaping system for forming a near-field point ring spot is proposed. In order to solve the problem that the conical lens in the beam shaping element presents Bessel distribution in the near field and forms a ring distribution in the far field when shaping the Gaussian beam, this scheme uses the front focal plane of the focusing mirror after beam combining to coincide with the back focal plane of the conical lens, and realizes a ring distribution on the back focal plane of the focusing mirror, which reduces the optical path, makes the optical path adjustment simpler, reduces the space occupied by the optical path, is conducive to the miniaturization of the laser, and can make the best use of the good single-mode beam quality of the green laser; the formed spot has clear edges and high power density, which can achieve deep fusion welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0016] Figure 1 It is a schematic structural diagram of the overlap between the rear focal plane of the optical shaping element and the front focal plane of the focusing mirror in the composite light spot shaping system described in the embodiment.

[0017] Figure 2 It is a schematic diagram of the structure in which the conical lens in the composite light spot shaping system described in the embodiment can be translated along the optical axis.

[0018] Figure 3 It is a schematic structural diagram of the overlap of the rear focal plane of the conic lens and the front focal plane of the focusing lens in the composite spot shaping system described in the embodiment.

[0019] Figure 4 Schematic diagram of the comparison between the output pulse and the spot energy distribution of the composite spot shaping system described in the embodiment. DETAILED DESCRIPTION

[0020] In order to facilitate the understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on another element, or there can be one or more centered elements therebetween. When an element is described as "electrically connected" to another element, it can be directly connected to another element, or there can be one or more centered elements therebetween. The orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "bottom", etc. used in this specification is based on the orientation or positional relationship shown in the accompanying drawings, only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0021] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0022] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0023] like Figure 1 As shown, the first light source 171 is used to emit a first light beam, and the first light beam is transmitted in a first channel; the second light source 172 is used to emit a second light beam, and the second light beam is transmitted in a second channel, and the first channel does not completely overlap with the second channel; the first light beam is emitted by the first light source 171, and the channel where it is located is the first channel; the second light beam is emitted by the second light source 172, and the channel where it is located is the second channel, the light-emitting positions of the first light source 171 and the second light source 172 are different, and the channels do not completely overlap.

[0024] In order to achieve spot shaping, a beam shaping element 21 is arranged in the channel. The beam shaping element 21 is arranged in the first channel and / or the second channel, and is used to adjust the energy distribution of the first beam and / or the second beam; the beam shaping element is arranged in the first channel, and is used to adjust the energy distribution of the first beam, thereby adjusting the first light spot formed by the first beam, and cooperating with the second light spot formed by the second beam to form a composite light spot; it can be understood that the beam shaping element 21 can also be arranged in the second channel, such as Figure 1 As shown, it is used to adjust the energy distribution of the second light beam, and then adjust the second light spot formed by the second light beam, and form a composite light spot with the first light spot formed by the first light beam; the beam displacement element 21 can also be arranged in the first channel and the second channel, and adjust the energy distribution of the second light beam and the first light beam respectively, and then adjust the second light spot formed by the second light beam and the first light spot formed by the first light beam respectively, and comprehensively adjust the composite light spot formed by the first light spot and the second light spot.

[0025] In order to combine the first light spot and the second light spot to form a composite light spot, it is necessary to combine the second light beam and the first light beam using a beam combiner 20. The beam combiner 20 is used to receive the first light beam transmitted through the first channel and the second light beam transmitted through the second channel, and combine the first light beam and the second light beam. The beam combining effect of the beam combiner affects the overlap of the first light spot and the second light spot.

[0026] The present application also includes a first focusing mirror 15. The first focusing mirror 15 is arranged at the output end of the beam combiner, and is used to converge the composite light beam formed by combining the first light beam and the second light beam, and the converged first light beam and the second light beam act on the processing surface 16. Since the first light beam and the second light beam are both Gaussian distributed laser beams, the light spot becomes larger as the optical path increases. Therefore, it is necessary to set the first focusing mirror 15 to converge the light spot. In particular, based on the imaging law of the first focusing mirror 15, the first focusing mirror 15 also plays the role of light field conversion in the present application.

[0027] Compared with the existing solutions, this application has at least the following advantages: 1. The present application realizes the coupling output of the second light beam and the first light beam in space, so that the light beam can be reused, thereby improving the energy utilization rate; 2. The present application adopts a beam shaping element to shape the second beam and / or the first beam, thereby changing the shape of the light spot and forming a preheating light spot, which can effectively suppress the spatter formed during processing.

[0028] Optionally, the beam shaping element 21 can be translated along the optical axis to form a variable composite light spot on the processing surface. One embodiment is that an aconical lens is arranged as the beam shaping element 21 on the first channel where the first light beam is located, and plays the role of shaping the Gaussian distribution of the first light beam into an annular distribution on the processing surface. By translating the position of the aconical lens in the channel along the optical axis, the size of the annular light spot formed by the first light beam on the processing surface can be changed, and then the size of the annular light spot in the combined spot ring light spot can be changed, so as to realize the setting of an adjustable spot ring light spot; one embodiment is, as Figure 2 As shown, the aconic lens is arranged as a beam shaping element 21 on the second channel where the second beam is located, and plays the role of shaping the Gaussian distribution of the second beam into an annular distribution on the processing surface. By translating the position of the aconic lens in the channel along the optical axis, the size of the annular spot formed by the second beam in the far field can be changed, and then the size of the annular spot in the spot ring spot after beam combination can be changed, so as to achieve the setting of an adjustable spot ring spot; one embodiment is that the aconic lens is arranged as a beam shaping element 21 on the first channel where the first beam is located and the second channel where the second beam is located, respectively, and plays the role of shaping the Gaussian distribution of the first beam and the second beam on the processing surface into an annular distribution. By translating the position of the aconic lens in the channel along the optical axis where each beam is located, the size of the annular spot formed by the first beam and the second beam in the far field can be changed, and then the size of the annular spot after beam combination can be changed, so as to achieve the setting of an adjustable annular spot.

[0029] Optionally, the beam shaping element 21 includes an aconic lens. The beam shaping element 21 is not limited to an aconic lens for realizing annular light distribution, and a DOE (diffractive optical element), a homogenizing lens, a curved mirror, a microlens array, etc. may be used to form the laser beam into other light spot shapes such as a homogenized light spot, a rectangular light spot, a regular hexagonal light spot, etc.

[0030] Optionally, the rear focal plane of the conical lens coincides with the front focal plane of the first focusing mirror, which can be used to form a light spot with clear edges on the processing surface 16. One embodiment is that the conical lens can not always move along the optical axis in the channel, but is given a specific position, that is, the rear focal plane of the conical lens coincides with the front focal plane 211 of the first focusing mirror 15. Through optical simulation, it can be known that the Gaussian distribution light beam does not immediately become a ring-shaped distribution light beam after passing through the conical lens, but first presents a Bessel distribution, and can only become a ring-shaped distribution light beam in the far field. In the scheme of forming a ring distribution in the far field, the optical path is longer and more space is required; the annular light spot formed in the far field is more divergent. Therefore, the first focusing mirror 15 is set, and the front focal plane 211 of the first focusing mirror 15 is coincident with the rear focal plane of the conical lens, so that a ring-shaped light spot with clear boundaries can be formed on the rear focal plane of the first focusing mirror.

[0031] In one embodiment, an axicon is arranged on the first channel, and the rear focal plane of the axicon coincides with the front focal plane 211 of the first focusing mirror 15. At this time, at the rear focal plane of the first focusing mirror 15, the second light beam presents a Gaussian distribution, and the first light beam presents an annular distribution; in the composite light spot formed by the composite light beam on the rear focal plane of the first focusing mirror 15, the second light spot presents a circle at the center; the first light spot presents a ring with clear edges; the composite light beam presents a Gaussian + annular distribution, and the composite light spot presents a point ring distribution.

[0032] One embodiment is, Figure 3 As shown, the axicon is arranged on the second channel, and the rear focal plane of the axicon coincides with the front focal plane 211 of the first focusing mirror 15. At this time, at the rear focal plane of the first focusing mirror 15, the first light beam presents a Gaussian distribution, and the second light beam presents a ring distribution; in the composite light spot formed by the composite light beam on the rear focal plane of the first focusing mirror 15, the first light spot presents a circle at the center; the second light spot presents a ring with clear edges; the composite light beam presents a Gaussian + ring distribution, and the composite light spot presents a point ring distribution.

[0033] In one embodiment, the axicons are respectively arranged on the first channel and the second channel, and the rear focal planes of the two axicons coincide with the front focal plane 211 of the first focusing mirror 15. At this time, at the rear focal plane of the first focusing mirror 15, the first light beam and the second light beam both present annular distribution; in the composite light spot formed by the composite light beam on the rear focal plane of the first focusing mirror 15, the first light spot and the second light spot present annular shapes with clear edges; the composite light beam presents annular distribution, and the composite light spot presents annular distribution.

[0034] The scheme in which the rear focal plane of the conical lens and the front focal plane of the first focusing mirror 15 coincide with each other forms an annular light spot with a shorter optical path, clearer edges and higher power density, which can be suitable for situations with higher requirements on power density.

[0035] Optionally, when the rear focal plane of the conical lens coincides with the front focal plane of the first focusing mirror 15, a ring-shaped light spot with clear edges will be formed on the rear focal plane of the first focusing mirror 15. Therefore, in the scheme where the rear focal plane of the conical lens coincides with the front focal plane of the first focusing mirror 15, the processing surface 16 coincides with the rear focal plane of the first focusing mirror.

[0036] It is understandable that when the beam shaping element 21 is movably disposed in the optical path, the optical path of the first light beam and the second light beam between the rear focal plane of the beam shaping element 21 and the front focal plane of the first focusing mirror is not less than the focal length of the first focusing mirror. When the beam shaping element 21 is movably disposed in the optical path, there is no longer a confocal requirement for the beam shaping element 21 and the first focusing mirror 15. At this time, the first focusing mirror only plays a focusing role in the optical path. It is understandable that the focusing mirror can only play a focusing effect on the light spot shaped by the beam shaping element when the distance between the position where the beam shaping element 21 forms a set light spot shape and the first focusing mirror 15 is greater than 2 times the focal length of the first focusing mirror 15.

[0037] Optionally, the composite light spot shaping system further includes a laser source 11, a half-wave plate 12 and a frequency doubling crystal 14 which are arranged in sequence, the laser source 11 is used to output a fundamental frequency beam, the half-wave plate 12 is used to change the polarization direction of the fundamental frequency beam, and the frequency doubling crystal 14 is used to frequency doubling the fundamental frequency beam whose polarization direction is changed by the half-wave plate, wherein the phase matching direction of the frequency doubling crystal 14 is related to the polarization direction of the incident light, therefore, by slowly rotating the half-wave plate 12, the frequency doubling efficiency of the frequency doubling crystal 14 can be changed. At the same time, due to the frequency doubling characteristics of the frequency doubling crystal 14, the frequency doubling crystal cannot completely convert the fundamental frequency beam into a frequency doubling beam, therefore, the frequency doubling crystal 14 outputs a composite beam formed by the frequency doubling beam and the fundamental frequency beam that has not been frequency doubling.

[0038] Optionally, a beam splitter 17 is provided at the output end of the frequency doubling crystal 14 for splitting the frequency doubling beam and the baseband beam that has not been frequency doubling. The frequency doubling beam after the splitting is transmitted as the first beam in the first channel, and the second baseband beam after the splitting is transmitted as the second beam in the second channel. It can be understood that since the laser energy in the green light band can still maintain the single-mode beam quality when outputting at a high power of kilowatts, in order to better utilize the single-mode property of the frequency doubling laser in the first channel, when the frequency doubling beam formed by the frequency doubling crystal is in the green light band, such as Figure 1As shown, the beam shaping element 21 is only arranged in the first channel, and the beam splitting and combining process does not extend the original optical path of the second channel. The second channel is not provided with an optical element so that the optical path of the second channel where the doubled frequency beam is located is as short as possible, and the doubled frequency spot is located at the center of the composite spot. This is a better solution. In combination with the scheme in which the rear focal plane of the conical lens and the front focal plane of the first focusing mirror 15 overlap, the optical path of the second channel is reduced, and the advantage of the high single-mode quality of the doubled frequency beam can be more fully utilized. It can be understood that the beam shaping element 21 is arranged in the first channel and / or the second channel and is included in the solution of the present application.

[0039] Optionally, a second focusing mirror 13 is provided between the half-wave plate and the frequency doubling crystal, for converging the fundamental frequency light beam whose polarization direction is changed by the half-wave plate 12 and then injecting the light beam into the frequency doubling crystal 14 .

[0040] Optionally, the fundamental frequency beam output by the laser source 11 is formed by a composite of a continuous laser and a pulsed laser. The frequency doubling efficiency of the frequency doubling crystal 14 for continuous laser and pulsed laser of the same power is different, and the frequency doubling efficiency for the pulsed laser is related to the pulse width and repetition rate of the pulsed laser. Therefore, the wavelength component of the composite light spot can be comprehensively adjusted by adjusting the power of the fundamental frequency beam, the power ratio of the continuous laser and the pulsed laser, and the pulse width and repetition rate of the pulsed laser; and because the repetition rate of the pulsed laser reaches the kHz level, the frequency of the change when the instantaneous power of the pulsed laser is 0 and when the instantaneous power of the pulsed laser is maximum is in the kHz level. It can be known that the frequency doubling efficiency of the frequency doubling crystal 14 is different when the instantaneous power of the pulsed laser is 0 and when the instantaneous power of the pulsed laser is maximum, so the change in the wavelength component of the composite light spot can also reach an adjustment rate of the kHz level. Figure 4 The upper middle figure shows the variation of the output power of the fundamental frequency beam over time, and the lower figure shows the energy distribution of the composite light spot at the corresponding time, where the green line represents the energy distribution of the double frequency beam and the red line represents the energy distribution of the first beam. Figure 4 As shown, the power proportions of the frequency-doubled beam and the first beam are different when the instantaneous power of the pulsed laser is 0 and when the instantaneous power of the pulsed laser is at its maximum; the frequency of change of the power proportion of the frequency-doubled beam and the first beam is consistent with the repetition rate of the pulsed laser. The joint control of the half-wave plate and the repetition rate on the fundamental frequency beam enables the beams output by the first light source and the second light source to have more diverse wavelength component ratios and light output waveforms, thereby enabling the composite light spot used for shaping in the composite light spot shaping system proposed in this application to have more wavelength component ratios and time domain changes, adapting to more processing scenarios.

[0041] Compared with the prior art, this application has at least the following advantages: 1. The present application splits the frequency-doubled light beam and the un-frequency-doubled fundamental frequency light beam, shapes them, and then combines them for output, thereby utilizing the un-frequency-doubled fundamental frequency light that is dispersed as stray light in the existing solution, thereby improving the energy utilization rate; 2. Use the beam shaping element to shape the doubled frequency beam and the second fundamental frequency beam that has not been doubled frequency. The wavelength distribution and shape distribution of the formed composite light spot can be adjusted to adapt to a variety of processing environments; 3. A concise spot shaping system for forming a near-field point ring spot is proposed. In view of the problem that the conical lens in the beam shaping element presents a Bessel distribution in the near field and a ring distribution in the far field when shaping the Gaussian beam, this solution uses the front focal plane of the focusing mirror after beam combination to coincide with the rear focal plane of the conical lens, and realizes a ring distribution on the rear focal plane of the focusing mirror, which reduces the optical path, makes the optical path adjustment simpler, reduces the space occupied by the optical path, is conducive to the miniaturization of the laser, and can make the most of the good single-mode beam quality of the green laser; the formed spot has clear edges and high power density, which can achieve deep fusion welding. Therefore, this application effectively overcomes the various shortcomings of the prior art and has a high industrial utilization value.

[0042] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A composite spot shaping system, characterized in that: The light spot shaping system comprises: A first light source, configured to emit a first light beam, wherein the first light beam is transmitted in a first channel; a second light source, configured to emit a second light beam, wherein the second light beam is transmitted in a second channel, and the optical paths of the first channel and the second channel are different; a beam shaping element, disposed in the first channel and / or the second channel, for shaping the first light beam and / or the second light beam; a beam combiner, disposed at the beam output ends of the first channel and the second channel, to receive the first beam transmitted through the first channel and the second beam transmitted through the second channel, and combine the first beam and the second beam; and A first focusing mirror is arranged at the output end of the beam combiner, and is used to converge the first light beam and the second light beam after being combined, so that the converged first light beam and the second light beam act on the processing surface.

2. The composite spot shaping system according to claim 1, characterized in that: The beam shaping element can be translated along the optical axis to form a variable composite light spot on the processing surface.

3. The composite spot shaping system according to claim 1, characterized in that: The beam shaping element includes an axicon.

4. The composite light spot shaping system according to claim 3, characterized in that: The rear focal plane of the axicon coincides with the front focal plane of the first focusing mirror.

5. The composite spot shaping system according to claim 4, characterized in that: The processed surface coincides with the rear focal plane of the first focusing mirror.

6. The composite light spot shaping system according to claim 2, characterized in that: An optical path of the first light beam and the second light beam between a rear focal plane of the beam shaping element and a front focal plane of the first focusing mirror is not less than a focal length of the first focusing mirror.

7. The composite light spot shaping system according to claim 1, characterized in that: The composite light spot shaping system also includes a laser source, a half-wave plate and a frequency doubling crystal which are arranged in sequence. The laser source is used to output a fundamental frequency beam, the half-wave plate is used to change the polarization direction of the fundamental frequency beam, and the frequency doubling crystal is used to frequency double the fundamental frequency beam whose polarization direction is changed by the half-wave plate, and output a frequency doubling beam and a second fundamental frequency beam which has not been frequency doubling.

8. The composite light spot shaping system according to claim 7, characterized in that: A beam splitter is provided at the output end of the frequency doubling crystal for splitting the frequency doubling light beam and the second fundamental frequency light beam that has not been frequency doubling. The split frequency doubling light beam is transmitted as the first light beam in the first channel, and the split second fundamental frequency light beam that has not been frequency doubling is transmitted as the second light beam in the second channel.

9. The composite light spot shaping system according to claim 7, characterized in that: A second focusing mirror is arranged between the half-wave plate and the frequency doubling crystal, and is used to converge the fundamental frequency light beam whose polarization direction is changed by the half-wave plate and then inject it into the frequency doubling crystal.

10. The composite light spot shaping system according to claim 7, characterized in that: The fundamental frequency light beam output by the laser source is formed by combining continuous laser light and pulsed laser light.

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